Define the word defect. Does it mean unnatural? If you're born without the ability to see then your ability to see is certainly defective but that isn't unnatural for your biology. It is the default of your biology. Your biology may be the reason that you have less than perfect vision or no vision. If you're born without the ability to reproduce that is the default of your biology. We use medicine and technology like eye glasses and in vitro to make up for our biological short falls and you dumb Bigots are like an asshole screaming at a guy going to the optometrist because you think his biology means he should have to walk around bumping into shit for the rest of his life.
You're so stupid that you don't know how dumb that assertion is. We weren't molded out of clay to be a certain way. A million years ago a chimpanzee was our brother. We got the genetic code for limbs from our fish ancestor over 50 million years ago. We evolved here through random mutation, adaptation and luck. There is no default. Our evolution hasn't stopped.
Sure I'm not Marty. I'm also not deeply enjoy myself as I'm doing it.